Secondary School (English Medium) (5 to 8) Class 8 - CBSE Question Bank Solutions

Explain why fossil fuels are exhaustible natural resources.

Describe characteristics of coke.

Make a labelled diagram of a candle flame.

Abida and Ramesh were doing an experiment in which water was to be heated in a beaker. Abida kept the beaker near the wick in the yellow part of the candle flame. Ramesh kept the beaker in the outermost part of the flame. Whose water will get heated in a shorter time?

Word game: Use the clues to work out the words.

Across

3. Protruding voice box in boys

4. Glands without ducts

7. Endocrine gland attached to brain

8. Secretion of endocrine glands

9. Pancreatic hormone

10. Female hormone

Down

1. Male hormone

2. Secretes thyroxin

3. Another term for teenage

5. Hormone reaches here through blood stream

6. Voice box

7. Term for changes at adolescence

Friction produces ______.

Voice of which of the following is likely to have minimum frequency?

Identify the part which vibrates to produce sound in the following instrument.

Dholak

Identify the part which vibrates to produce sound in the following instrument.

Sitar

Identify the part which vibrates to produce sound in the following instrument.

Flute

Sketch larynx and explain its function in your own words.

The passage of an electric current through a solution causes ______ effects.

If you pass current through copper sulphate solution, copper gets deposited on the plate connected to the ______ terminal of the battery.

The process of depositing a layer of any desired metal on another material by means of electricity is called ______.

Name three liquids, which when tested in the manner shown in Figure, may cause the magnetic needle to deflect.

Prepare a list of objects around you that are electroplated.

The process that you saw in the image is used for the purification of copper. A thin plate of pure copper and a thick rod of impure copper are used as electrodes. Copper from impure rod is sought to be transferred to the thin copper plate. Which electrode should be attached to the positive terminal of the battery and why?

Which of the following cannot be charged easily by friction?

Like charges attract each other.

Explain why a charged body loses its charge if we touch it with our hand.